CHICAGO – Police said Thursday they think more than one person carried out the slayings of five people found dead Wednesday afternoon inside a ransacked house on Chicago’s South Side.

Authorities have not identified any suspects or determined a motive, but police are confident the killings were not a random act, said Chicago Police Commander Eddie Welch.

“They were definitely targeted,” he said at a news conference Thursday afternoon at police headquarters.

Further, he said it was obvious that whoever carried out the crime spent a lot of time in the house.

“There was a lot of damage to this residence, at all levels of this residence,” Welch said.

Authorities are following up a host of leads and have not ruled out any motive, including whether the slayings were or were not gang related, officials said.

The killings come at a time of heightened concern in the city about a recent spate of gun violence. The five deaths brought the number of people who have been shot to death in Chicago in less than a week to 15.

In the days before the discovery of the bodies, more than three dozen people were shot. Many of those shootings were gang-related.

Chicago Mayor Richard Daley told The Associated Press Thursday he plans to meet Friday with more than two dozen officials from religious groups, police, schools and social service agencies to talk about what’s causing the violence and how to stop it.

But the mayor added he doesn’t believe the recent violence is tarnishing Chicago’s reputation.

Associated Press Writer Deanna Bellandi contributed to this report